Curriculum for Plant Biology 17 Kingdom Monera and Viruses. Prerequisite Skills. Skills. Framework Standard(s) Biology

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1 Plant Biology 17 Kingdom Monera and Viruses I. Introduction to Bacteria A. symbiotic relationships 1. mutualism between luminescent bacteria and flash-light fish B. Ancient organisms 1. known as fossils 3.5 billion years old C. Number of species 1. about 4,000 species known 2. occur in almost any natural habitat 3. some species may have many different strains D. Pathogenic or Harmless? 1. more than 90% either harmless or beneficial to humans II. Features of the Kingdom Monera A. Prokaryotic cells B. Colonies or filaments C. Motility 1. most nonmotile 2. some possess bacterial flagella 3. others move by gliding motion Biology 2.2 Differentiate between prokaryotic cells and eukaryotic cells, in terms of their general structures and degrees of complexity. 3.9 Recognize that while viruses lack cellular structure, they have the genetic material to invade living cells. 5.3 Describe how the taxonomic system classifies living things into domains (eubacteria, archaebacteria, and eukaryotes) and kingdoms (animals, plants, fungi, etc.). 6.2 Use a food web to identify and distinguish producers, consumers, and decomposers, and explain the transfer of energy through trophic levels. Students should be able to: 1. Know the basic forms of bacteria. 2. Explain how a prokaryotic cell differs from a eukaryotic cell and why prokaryotic organisms are difficult to classify. 3. Learn the forms of nutrition in bacteria. 4. Know at least ten bacteria useful to humans, and understand how they are useful. 5. Understand the various ways in which disease bacteria are transmitted. 6. Describe how each type of disease bacterium functions in causing disease. 7. Learn Koch s Postulates. 8. Know how the major groups of bacteria differ from one another in form, pigmentation, and reproduction. 9. Know how viruses differ from bacteria in form and reproduction. 1. Virus are subcellular particles. 2. Bacteria are cellular in nature. Page 1 of 15

2 D. Nutrition 1. absorption of food in solution 2. chemosynthesis E. Reproduction 1. predominantly asexual by binary fission 2. genetic recombination in several groups III. Cellular Detail and Reproduction A. Cell structure 1. prokaryotic a. no membrane -bound organelles 2. nucleoid a. single chromosome (long, very condensed DNA molecule in ring form) 3. plasmids a. small, circular, extrachromosomal DNA molecules B. Reproduction 1. by binary fission a. a bacterium may undergo fission Page 2 of 15

3 every minutes 2. conjugation a. part of a chromosome is transferred from donor cell to recipient through pilus 3. transformation a. living cell picks up fragments of DNA released by dead cells 4. transduction a. fragments of DNA carried from one cell to another by viruses IV. Size, Form, and Classification of Bacteria A. Size 1. most are less than 2-3 um in diameter, the smallest being around 0.15 um B. Form 1. cocci a. spherical 2. bacilli Page 3 of 15

4 a. rod-shaped or cylindrical 3. spirilli a. helical or spiral C. Classification 1. based on reaction to a dye 2. two categories a. gram-positive b. gram-negative 3. stain named after Christian Gram a. made observation in 1884 V. Subkingdom Archaebacteriobionta: The Archaebacteria A. Distinctive characteristics 1. unique sequence of bases in RNA 2. cell walls lack muramic acid 3. production of distinctive lipids B. The methane bacteria 1. anaerobic 2. produce methane from carbon dioxide and hyrdrogen C. The salt bacteria Page 4 of 15

5 1. thrive in high salinity 2. carry on photosynthesis with the aid of bacterial rhodopsin D. The sulpholobus bacteria 1. occur in sulphur hot springs E. Human relevance of the archaebacteria 1. methane production for fuel VI. Subkingdom Eubacteriobionta: The True Bacteria (Division Eubacteriophyta) A. Class Eubacteriae the unpigmented, purple, and green sulphur bacteria 1. heterotrophic bacteria a. saprobes b. parasites 2. autrophic bacteria a. photosynthetic bacteria 1. some produce oxygen, others sulphur Page 5 of 15

6 2. pigments located in thylakoids a. bacteriochlorophyll or chlorobium chlorophyll b. chemoautotrphic bacteria 1. obtain energy through oxidation of reduced inorganic groups (NH 3, H 2 S) 2. examples: iron, sulphur, and hydrogen bacteria 3. human relevance of the unpigmented, purple, and green sulphur bacteria a. compost and composting b. true bacteria and disease 1. modes of access of disease bacteria a. access from the air ( strep throat, chlamydias) Page 6 of 15

7 b. access through contamination of food & drink 1. Salmonella food poisoning 2. staphyloccus food poisoning 3. legionnaire s disease 4. botulism c. access through direct contact 1. syphilis and gonorrhea 2. anthrax 3. brucellosis d. access through wounds 1. tetanus 2. gas gangrene e. access through bites of insects and other organisms 1. bubonic plague (the Black Death) 2. tularemia 3. rickettsias Page 7 of 15

8 4. pleuropneumonialike organism (PPLOs) 5. lyme disease 2. Koch s postulates a. microorganism must be present in all cases of the disease b. microorganism must be isolated from the victim in pure culture c. microorganism from pure culture, when injected into susceptible host must produce the disease in the host d. microorganism must be isolated from the experimentally infected host & grown in pure culture c. true bacteria useful to humans Page 8 of 15

9 1. biological control a. Bacillus thuringiensis 1. control of caterpillars b. Bacillus thuringiensis (var. israelensis) c. Bacillus popilliae 1. control of Japanese Beetle grubs 2. bioremediation a. break down of nitroglycerin & trinitrotoluene b. Pseudomonas capacia 1. breakdown of oil spills & chemical dumps d. other useful bacteria 1. research into chemistry of vision 2. dairy industry Page 9 of 15

10 3. digestive system aids (Lactobacillus acidophilus) 4. production of metabolic wastes with industrial use 5. food production B. Class Cyanobacteria blue-green bacteria 1. Introduction a. pigments 1. chlorophyll a 2. phycocyanin 3. phycoerythrin b. can both fix nitrogen and produce oxygen 2. distribution a. widely distributed in fresh and marine waters b. some precipitate carbonate deposits (travertine) 3. form, metabolism, and reproduction a. form 1. cells often occur in chains or Page 10 of 15

11 hair-like filaments 2. some species occur as colonies 3. color varies depending on pigments present, although half are blue-green b.metabolism 1. store carbohydrates, lipids, and the nitrogenous cyanophyein c. reproduction 1. new cells formed by fission 2. new colonies may be formed by fragmentation at a. heterocysts (nitrogen-fixing cells) b. akinetes 3. genetic recombination 4. Blue-green bacteria, chloroplasts, and oxygen a. symbiotic origin of chloroplasts from Page 11 of 15

12 blue-green bacteria 1. blue-green bacteria occur symbiotically & function essentially as chloroplasts in host organism b. speculation that chloroplasts originated as prochlorobacteria 5. human relevance of the blue-green bacteria a. occur at bottom of food chains b. production of blooms c. poisons d. Spirulina used as food e. undesirable effects in human water supplies f. nitrogen fixation C. Class Prochlorobacteriae The Prochlorobacteria Page 12 of 15

13 1. discovered living on sea squirts (1976) 2. have chlorophylls a and b, but not phycobilins 3. thylakoid membranes double, unlike thylakoids of blue -green bacteria 4. one very abundant form found at depth of 100 m in ocean waters VII. Viruses A. Introduction 1. smallpox a. an often fatal, communicable disease b. has now been eradicated 2. vaccination against smallpox a. performed by Edward Jenner, a country physician, in 1796 B. Size and Structure 1. vary in diameter from 15 to 300 nm Page 13 of 15

14 2. consist of nucleic acid core surrounded by a protein coat a. nucleic acid may be DNA or RNA, but never both b. protein coat often has 20 sides, resembling tiny geodesic domes C. Bacteriophages 1. viruses that attack bacteria D. Viral Reproduction 1. viruses replicate only at the expense of their host cells 2. viruses must become attached to a susceptible cell 3. once inside the host cell, their DNA or RNA directs the synthesis of new viral particles 4. some viruses mutate rapidly 5. viruses may affect the metabolism of their host cells 6. infected cells can Page 14 of 15

15 produce interferon which protects uninfected cells E. Human Relevance of Viruses 1. numerous diseases caused by viruses 2. AIDS, caused by a retrovirus called HIV 3. production of vaccines 4. viroids and prions Page 15 of 15